1. Field of the Invention
The present invention generally relates to medical devices, methods, and systems. More specifically, the present invention provides techniques for selectively heating and shrinking tissues, particularly for the noninvasive treatment of urinary incontinence and hernias, for cosmetic surgery, and the like.
Urinary incontinence arises in both women and men with varying degrees of severity, and from different causes. In men, the condition occurs almost exclusively as a result of prostatectomies which result in mechanical damage to the sphincter. In women, the condition typically arises after pregnancy where musculoskeletal damage has occurred as a result of inelastic stretching of the structures which support the genitourinary tract. Specifically, pregnancy can result in inelastic stretching of the pelvic floor, the external sphincter, and most often, to the tissue structures which support the bladder and bladder neck region. In each of these cases, urinary leakage typically occurs when a patient""s intra-abdominal pressure increases as a result of stress, e.g. coughing, sneezing, laughing, exercise, or the like.
Treatment of urinary incontinence can take a variety of forms. Most simply, the patient can wear absorptive devices or clothing, which is often sufficient for minor leakage events. Alternatively or additionally, patients may undertake exercises intended to strengthen the muscles in the pelvic region, or may attempt behavior modification intended to reduce the incidence of urinary leakage.
In cases where such noninterventional approaches are inadequate or unacceptable, the patient may undergo surgery to correct the problem. A variety of procedures have been developed to correct urinary incontinence in women. Several of these procedures are specifically intended to support the bladder neck region. For example, sutures, straps, or other artificial structures are often looped around the bladder neck and affixed to the pelvis, the endopelvic fascia, the ligaments which support the bladder, or the like. Other procedures involve surgical injections of bulking agents, inflatable balloons, or other elements to mechanically support the bladder neck.
Each of these procedures has associated shortcomings. Surgical operations which involve suturing of the tissue structures supporting the urethra or bladder neck region require great skill and care to achieve the proper level of artificial support. In other words, it is necessary to occlude or support the tissues sufficiently to inhibit urinary leakage, but not so much that intentional voiding is made difficult or impossible. Balloons and other bulking agents which have been inserted can migrate or be absorbed by the body. The presence of such inserts can also be a source of urinary tract infections. Therefore, it would be desirable to provide an improved therapy for urinary incontinence.
A variety of other problems can arise when the support tissues of the body have excessive length. Excessive length of the pelvic support tissues (particularly the ligaments and fascia of the pelvic area) can lead to a variety of ailments including, for example, cystocele, in which a portion of the bladder protrudes into the vagina. Many hernias are the result of a strained, torn, and/or distended containing tissue, which allows some other tissue or organ to protrude beyond its contained position. Cosmetic surgeries are also often performed to decrease the length of support tissues. For example, abdominoplasty (often called a xe2x80x9ctummy tuckxe2x80x9d) is often performed to decrease the circumference of the abdominal wall. The distortion of these support tissues may be due to strain, advanced age, congenital predisposition, or the like.
Unfortunately, many support tissues are difficult to access, and their tough, fibrous nature can complicate their repair. As a result, the therapies now used to improve or enhance the support provided by the ligaments and fascia of the body often involve quite invasive surgical procedures.
For these reasons, it would be desirable to provide improved devices, methods, and systems for treating fascia, tendons, and the other support tissues of the body. It would be particularly desirable to provide improved noninvasive or minimally invasive therapies for these support tissues, especially for the treatment of urinary incontinence in men and women. It would further be desirable to provide treatment methods which made use of the existing support structures of the body, rather than depending on the specific length of an artificial support structure.
2. Description of the Background Art
U.S. Pat. No. 5,423,811 describes a method for RF ablation using a cooled electrode. U.S. Pat. Nos. 5,458,596 and 5,569,242 describe methods and an apparatus for controlled contraction of soft tissue. An RF apparatus for controlled depth ablation of soft tissue is described in U.S. Pat. No. 5,514,130.
U.S. Pat. No. 4,679,561 describes an implantable apparatus for localized heating of tissue, while U.S. Pat. No. 4,765,331 describes an electrosurgical device with a treatment arc of less than 360 degrees. An impedance and temperature generator control is described in U.S. Pat. No. 5,496,312. Bipolar surgical devices are described in U.S. Pat. Nos. 5,282,799, 5,201,732, and 728,883.
The present invention provides devices, methods, and systems for shrinking of collagenated tissues, particularly for treating urinary incontinence in a noninvasive manner. In contrast to prior art techniques, the present invention does not rely on implantation of balloons or other materials, nor does it rely on suturing, cutting, or other direct surgical modifications to the natural support tissues of the body. Instead, the present invention directs energy to a patient""s own support tissues. This energy gently heats fascia and other collagenated support tissues, causing them to contract without substantial necrosis of adjacent tissues. The energy will preferably be applied through a large, cooled electrode having a substantially flat electrode surface. Such a cooled plate electrode is capable of directing electrical energy through an intermediate tissue and into fascia, while the cooled electrode surface prevents injury to the intermediate tissue. Ideally, the plate electrode comprises an electrode array which includes several discrete electrode surface segments so that the current flux can be varied to selectively target and evenly heat the fascia. In some embodiments, the tissue is heated between a pair of parallel cooled electrode surfaces, the parallel surfaces optionally being planar, cylindrical, spherical, or the like.
In a first aspect, the present invention provides a probe for therapeutically heating a target tissue of a patient body through an intermediate tissue. The probe comprises an electrode with an electrode surface which is engagable against the intermediate tissue. The electrode surface is substantially flat, and a cooling system is coupled to the electrode. The cooling system allows the electrode surface to cool the engaged intermediate tissue while an electrical current flux from the electrode surface therapeutically heats the target tissue.
The electrode surface will generally be sufficiently flat to direct the current flux through the cooled intermediate tissue and into the target tissue while the cooling system maintains the intermediate tissue at or below a maximum safe tissue temperature. To direct the current flux, heating may be provided between a pair of electrode surfaces, the electrode surfaces typically being separated by a distance from about ⅓ to about 1.0 times the least width of the electrodes. In many embodiments, a temperature sensor will monitor the temperature of the target tissue or the intermediate tissue. A control system will often selectively energize the electrode and/or cooling system in response to the monitored temperature.
In another aspect, the present invention provides a probe for applying energy to fascia from within the vagina of a patient body. The fascia is separated from the vagina by vaginal mucosa. The probe comprises a probe body having a proximal end and a distal end, the probe having a length and a cross-section selected to permit introduction into the vagina. An energy transmitting element is mounted to the probe body. The transmitting element is capable of transmitting sufficient heating energy through the vaginal mucosa to heat and contract the fascia. A cooling system is disposed adjacent to the transmitting element. The cooling system is capable of maintaining the vaginal mucosa adjacent the probe below a maximum safe temperature when the fascia is heated by the transmitting element.
The present invention also provides a method for shrinking a target collagenated tissue within a patient body through an intermediate tissue. The method comprises directing energy from a probe, through the intermediate tissue, and into the target tissue. The energy heats the target tissue so that the target tissue contracts. The intermediate tissue is cooled with the probe to avoid injuring the intermediate tissue when the target tissue is heated by the probe.
In yet another aspect, the present invention provides a method for directing energy into a target tissue of a patient body through an intermediate tissue. The method comprises electrically coupling a first electrode to the patient body. A second electrode is electrically coupled to the intermediate tissue, the second electrode being mounted on a probe. The intermediate tissue is cooled by the probe, and an electrical potential is applied between the first and second electrodes. An electrode surface of the second electrode is sufficiently large and flat to provide a current flux that extends through the cooled intermediate tissue so that the current flux heats the target tissue.
In yet another aspect, the present invention provides a method for therapeutically heating a target zone of a tissue within a patient body. The method comprises engaging a tissue adjacent to the target zone with a probe. The adjacent tissue is pre-cooled with the probe, and the target zone is heated by directing energy from the probe, through the pre-cooled adjacent tissue, and into the target zone.
In another aspect, the present invention provides a kit for shrinking a target collagenated tissue within a patient body through an intermediate tissue. The kit comprises a probe having an energy transmitting element adapted to direct an energy flux through the intermediate tissue and into the target tissue. A cooling system is adjacent to the transmitting element to cool the intermediate tissue. The kit also includes instructions for operating the probe. The instructions comprise the steps of directing energy from the energy transmitting element of the probe, through the intermediate tissue, and into the target tissue so as to heat and shrink the target tissue. The intermediate tissue is to be cooled with the cooling system of the probe to avoid heating and injuring of the intermediate tissue when the target tissue is heated by the energy.
In a final aspect, the present invention further provides a method for teaching. The method comprises demonstrating cooling of a surface with a probe. Directing of energy from the probe is also demonstrated, the energy being directed through the surface and into tan underlying structure to effect shrinkage of the structure.